移动电源单芯片 2A,

NE6032移动电源单芯片三合一方案介绍NE6032是一款高性能、高可靠性的移动电源单芯片三合一方案。

它集成了电池管理、DC-DC变换和USB充电功能，并且支持USB快速充电、适配器充电和手动充电等多种充电方式。

下面将从方案特点、技术参数、应用场景和优势等方面进行介绍。

方案特点：1.移动电源单芯片三合一，简化了设计。

2.高度集成，减小了PCB板面积和系统成本。

3.支持多种充电方式，满足不同用户需求。

4.内置高精度ADC，实时监测电池电压和电流。

5.高效的DC-DC变换，提高了能量利用率。

6.低静态功耗，延长了电池使用寿命。

技术参数：1.输入电压范围：4.35V~5.5V。

2.输出电压范围：4.3V~5.25V。

3.输出电流：最大2A。

4.效率：高达90%。

5.充电方式：USB快速充电、适配器充电、手动充电。

6.温度范围：-40℃~85℃。

应用场景：优势：1.高度集成的单芯片设计，简化了电源电路的设计与布局，加快了产品的开发周期。

2.支持多种充电方式，满足用户不同的使用需求，提高了产品的灵活性和实用性。

3.高效的DC-DC变换，提高了能量的利用效率，延长了电池的使用时间。

4.内置高精度ADC，实时监测电池状态，为用户提供准确的电量信息。

5.低静态功耗，延长了电池的使用寿命，减少了充电次数。

总结：NE6032移动电源单芯片三合一方案是一款高性能、高可靠性的移动电源方案。

它通过集成电池管理、DC-DC变换和USB充电功能，满足了不同用户的需求。

该方案具有高效、稳定、灵活等优势，适用于各种移动设备的电源供应。

它的推出将为移动电源行业的发展带来新的机遇和挑战。

Integrated Charger/Boost Convertor with Power Path ControlFeaturesAdaptor Input Detection and Power Path Control Built-in 90m Ω Power Switch for Power Path ControlAdapter Input Over-Voltage ProtectionHigh Accuracy Switching Charger for 1 Cell Li-lon battery with Internal Compensation±0.5% Accuracy Battery Charger Output Voltage Charger Status Flag OutputAdapter Input Current Limit Controller with Built-in Current Sense ResistorTrickle Charging and Defective Battery Detec-tionHigh Efficiency Synchronous Boost Convertor Adjustable Output of Boost ConvertorEnable and Current Limit Control Pin for Boost Convertor.Output Short Circuit Protection for Boost Con-vertorAvailable for 4.2V/4.3V/4.35V Charge Voltage SettingAvailable for 2A/1.5A Charge CurrentSOP-8 (FD) PackageApplicationsMobile Battery BankGeneral DescriptionG5214 is an integrated charger/boost convertor with power path control for 1 cell Li-lon battery bank. The power path controller detects adapter input and control internal power switch of power path with over-voltage and over-current protection.The system operates in charger mode when adapter plug in. Charge current, battery voltage and adapter input current limit are regulated by constant off time buck controller with internal power MOSFET. The sys-tem enters trickle charge if battery voltage is too low. The charging stops if defective battery is detected. Charge Voltage has 2 options, 4.35V and 4.2V. Charge Current has 2 options, 2A and 1.5A. FLAG output indicates the charger status.The system operates in boost mode if adapter is absent and battery voltage is high enough. The output voltage is adjustable by external resistors with over current and short circuit protection. A 3-levels logic control the on/off and over-current of boost convertor.Ordering InformationORDER NUMBERMARKINGCHARGE CurrentCHARGE Voltage TEMP. RANGE PACKAGE (Green)G5214AF11U G5214A 2A 4.35V -40°C to +85°C SOP-8 (FD) G5214CF11U G5214C 2A 4.2V -40°C to +85°C SOP-8 (FD) G5214DF11U G5214D 1.5A 4.35V -40°C to +85°C SOP-8(FD) G5214FF11U G5214F 1.5A4.2V -40°C to +85°C SOP-8 (FD)Note: F1:SOP-8 (FD) 1: Bonding CodeU: Tape & ReelPin ConfigurationVADPVSYS EN/OCLX CSIP SOP-8 (FD)VBAT FLAGBTFB Note: Connect the thermal PAD to GND for proper function and excellent power dissipationAbsolute Maximum RatingsSupply Voltage (ADP to GND) . . . . . . . . .-0.3V to 6.5V Supply Voltage (ADP to GND, <30µS pulse ). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .-0.3V to 9V Supply Voltage (VSYS, VBAT to GND) . . . -0.3V to 6V CSIP to GND . . . . . . . . . . . . . . . . . . . . -0.3V to 6V LX to GND . . . . . . . . . . . . . . . . . . -0.5V to VSYS+0.5V Other Pins to GND. . . . . . . . . . . . . . . . . . . .-0.3V to 6V Thermal Resistance Junction to Ambient, (θJA )SOP-8 (FD) . . . . . . . . . . . . . . . . . . . . . . .132°C/W (1) SOP-8 (FD) (1in 2). . . . . . . . . . . . . . . . . . . . 108°C/W (2) Continuous Power Dissipation (T A = +25°C)SOP-8 (FD) . . . . . . . . . . . . . . . . . . . . . . .0.9W (1) SOP-8 (FD) (1in 2). . . . . . . . . . . . . . . . . . . . . . .1.2W (2) Thermal Resistance Junction to Case, (θJC )SOP-8 (FD) . . . . . . . . . . . . . . . . . . . . . . . . . . . 12°C/WStorage Temperature . . . . . . . . . . . . -65°C to +150°C Junction Temperature . . . . . . . . . . . . -10°C to +150°C Reflow Temperature (soldering, 10sec) . . . . . . .260°C ESD Protection (Human Body Mode) . . . . . . . . . . .2kVRecommended Operation ConditionsSupply Voltage (ADP to GND) . . . . . . . 4.8V to 5.5V Supply Voltage (VBAT to GND) . . . . . . .3V to 4.2V Operation Temperature (T A ) . . . . . . . -40°C to +85°CStress beyond those listed under “Absolute Maximum Ratings ” may cause permanent damage to the device.Note: (1): Please refer to Minimum Footprint PCB Layout Section. (2): Please refer to 1in 2 of 1oz PCB Layout Section.Electrical CharacteristicsADP =5V, V BAT =3.7V, T A =25°C, unless otherwise noted.The device is not guaranteed to function outside its operating conditions. Parameters with MIN and/or MAX limits are 100% tested at +25°C, unless otherwise specified.PARAMETER CONDITION MIN TYP MAX UNITSBattery Quiescent Current I VSYS =0 --- 500 700 µAVBAT=2.5V, Boost Convertor Stops --- 20 30 Battery Leakage CurrentVBAT=3.7V, Pull EN/OC low to shutdown--- 35 45 µAVBAT Rising2.62.752.9VBAT UVLO/ Trickle Charge ThresholdVBAT Falling 2.5 2.65 2.8VSwitch from VADP to VSYS --- 90 100m Ω Switch from VSYS to LX, V SYS =5V ---44 52 m Ω On-Resistance of Switches Switch from LX to GND, V SYS =5V --- 39 45 m Ω VSYS Short Circuit Blanking Time263443msVSYS Short Circuit Auto-Restart Time 177 238 300 msEN/OC input high threshold 4.5 --- ---EN/OC input low threshold --- --- 0.3 EN/OC Threshold EN/OC floating logic threshold 1.1 --- 3 V FLAG On Resistance ADP=5V---18 40 Ω FLAG Pin LeakageFLAG=6V--- 0.1 0.5 µA Thermal Shutdown Threshold Temperature Rising --- 150 --- °C Thermal Shutdown Hysteresis---25---°CAdapter Power Path Control ADP rising 4.65 4.74 4.83 V Adapter Power Good Threshold ADP falling 4.47 4.56 4.64 V ADP rising5.856.02 6.2 V Adapter OVP Threshold ADP falling 5.65 5.78 5.93 V G5214A/B/C, VSYS =0V 2.3 2.6 3.1Current Limit of Power SwitchG5214D/E/F, VSYS =0V1.82.1 2.6AElectrical Characteristics (continued)PARAMETER CONDITIONMINTYPMAX UNITSBOOST CONVERTORBTFB Output Voltage VBAT=3.0V~4.2V, I VSYS=0~2A 0.59 0.61 0.63VVSYS Short Current Limit VBAT>VSYS, R SNS=10mΩ, EN/OC floating 2.1 2.5 2.7 AReduction VSYS Short Current Limit VBAT>VSYS, R SNS=10mΩ, EN/OC input high 1.4 1.69 1.83 AVBAT=3.7V, EN/OC floating, R SNS=10mΩ 5.35 6.05 6.44VBAT=4.2V, EN/OC floating, R SNS=10mΩ 3.91 4.60 5.42Normal Inductor Peak Current LimitVBAT=3.0V, EN/OC floating, R SNS=10mΩ 5.42 6.40 7.49AVBAT=3.7V, EN/OC input high, R SNS=10mΩ 4.30 4.80 5.10VBAT=4.2V, EN/OC input high, R SNS=10mΩ 3.35 3.75 4.25Reduction Inductor Peak Current LimitVBAT=3.0V, EN/OC input high, R SNS=10mΩ 4.36 5.10 6.00AVBAT= 3.7V 1.2471.4341.649VBAT= 4.2V 1.421.6321.877Off-TimeVBAT=3V 1.0211.1641.339µsMinimum Off-Time --- 250 --- nsBoost Convertor OVP Threshold VSYS rising, reference to the normal boostoutput5 8 11 %Current Threshold of Asynchronous Converting R SNS=10mΩ100 150 300mASoft Start Time VBAT=3.7V, VSYS Rising to 4.8V --- 1 --- msBattery ChargerG5214C/F 4.1794.24.221Battery Charge Voltage AccuracyG5214A/D 4.328 4.35 4.372VG5214A/C, RSNS=10mΩ 1.83 2 2.17Charge Current AccuracyG5214D/F, RSNS=10mΩ 1.37 1.5 1.63AG5214A/C, RSNS=10mΩ110 250 350Trickle Charge Current AccuracyG5214D/F, RSNS=10mΩ80 200 300mAG5214A/C 1.822.3 Adapter Current Limit AccuracyG5214D/F 1.31.51.8AVSYS=5V, VBAT=3.7V 0.543 0.621 0.714VSYS=5V, VBAT=4.2V 0.329 0.379 0.436Off-TimeVSYS=5V, VBAT=2V 1.243 1.429 1.643µsMinimum Off-Time --- 250 --- nsDead Battery Detection Timeout Period 15415 17728 20387SVBAT rising, reference to the charge voltage 3.88 4 4.12Battery OVP ThresholdVBAT falling, reference to the charge voltage 2.43 2.5 2.58%Current Threshold of Asynchronous Converting R SNS=10mΩ-100 146 270mAMinimum Footprint PCB Layout SectionSOP-8 (FD)1in of 1oz PCB Layout SectionSOP-8 (FD)PIN NAMEPIN FUNCTION1 EN/OC Leave the pin floating set normal operating of boost convertor. Connect this pin to VBAT setthe current limit of boost convertor to 3/4 of normal value. Connect this pin to GND to shutdown the boost convertor.2 LX Connect the pin to output inductor.3 VSYS System output. Connect 33µFX2 capacitors to GND. 4VADPAC adapter input. Connect a capacitor to GND.5 FLAGCharger status indicator, open-drain output. The output is pulled low if the system is in charg-ing mode and battery is not fully charged. 6 BTFB Connect 2 resistors in series from VSYS to BTFB to GND to set the boost output votage 7 VBAT Battery input. Connect 20µF capacitors to GND. 8CSIPCurrent detection input.9 GND GroundBlock DiagramFunction DescriptionG5214 detects the plug-in of adapter, turns on power switch and decides boost/charging mode of the sys-tem automatically. If adapter is absent and battery voltage is high enough, the power switch is turned off and G5214 is in boost mode, the boost converter out-puts to system output source from battery. The power switch is turned on after adapter is plugged-in and detected. G5214 turns into charger mode after the power switch is fully turned on. In charger mode, sys-tem output is directly supply from adapter via the power switch, and the charger convertor supply charging current to the battery from system output. There are several protections of power path, boost convertor and charger convertor.Power Path ControlAdapter is detected if VADP is larger than power good threshold (4.74V with hysteresis) and smaller than OVP threshold (5.78V with hysteresis). After the de-tection of adapter, the power switch between VSYS and VADP turns on. The gate of NMOS switch rises slowly to minimize surge current of adapter. There is over-current protection for the power switch. If over-load occurs on VSYS, the switch gate is lowered down to keep the current flow through the switch in current limit to protect adapter and the switch.When adapter input OVP is detected, the power switch is shutdown immediately to keep VSYS below normal voltage range to protect the devices connected to VSYS from damaged by high voltage.After the gate of power switch rises high enough and no abnormal event is detected. The system gets into charger mode. If system isn’t in charger mode and the battery voltage is higher than VBAT UVLO threshold, the system operates in boost mode, otherwise the system is shutdown.Boost ConvertorIn boost mode, VSYS is boosted to the voltage setting by external resistors connected from VSYS to BTFB to GND. The BTFB pin is regulated to 0.61V. The con-troller of boost is constant off-time and the off-time is calculated by VSYS and VBAT to keep the switching frequency near 500kHz. Internal soft-start controls the rising time of VSYS output to about 1ms. There is OVP function of boost output.Boost convertor has current limit functions. If VSYS is lower than VBAT, the inductor current is limited to 2.5A. If VSYS is larger than VBAT, G5214 performs cycle by cycle peak inductor current limit. The current limit value is inversely proportion to VBAT, that makes output current limit changes slightly versus battery voltage.EN/OC pin controls the operation of boost convertor. The current limit is set to 3/4 of normal value when EN/OC is connected to VBAT. The boost convertor is shut down if EN/OC pin is pulled to GND. Leave the pin floating for normal operation.Charger ConvertorIn charger mode, adapter is connected to VSYS as the power of charger for 1 cell Li-lon battery. The system controls the battery voltage to 4.35V, 4.3V or 4.2V for G5214A/G5214D and G5214CG5214F, respectively. The charging current is lower down if adapter current is larger than a preset level. The current limit of total adapter current is 2A or 1.5A and current is sensed by internal resistor. The controller is constant off-time and the off-time is calculated by VSYS and VBAT to keep the switching frequency near 700kHz. The charger convertor is internal compensated.If battery voltage is below the UVLO threshold, the system is trickle charged with 15% of the normal charging current. The battery is determined as dead battery if battery voltage keeps under the UVLO threshold for over 17728S.G5214 has over-voltage protection for charger. The high and low side switched are turned off immediately if battery voltage goes over 4% of normal battery volt-age setting.The charge current is 2A or 1.5A. The adapter current is also limited to 2A or 1.5A. The current limits of power switch is 2.6A or 2.1A.Over-Current ProtectionsThe over-current protection of VSYS pin is auto-restart mode. If any of VSYS OCP event occurs (OCP of power switch or boost convertor) and lasting over 34ms, the system shutdown for 238ms and re-start again. The function keep the system temperature low even if VSYS is short. G5214 also have over-temperature protection. The whole system is shutdown if temperature rises over 150°C.Charger Status FlagWhen G5214 operates in charging mode, FLAG out-puts low if the battery is not fully charged. The FLAG pin outputs high impedance if system is not in charg-ing or the battery is fully charged.Application InformationInductor SelectionInductance between 3.3µH and 10µH is recommended. The RHZ is lower with large inductance. Select smaller inductance with larger VSYS capacitance to enlarge system bandwidth with the same output ripples at boost mode. It’s important to select inductor with maximum current to avoid saturation. Check both charger mode and boost mode for peak current.VSYS Capacitor SelectionThe recommended value of this capacitors is 33µFX2. This value maintain the boost controller loop at proper bandwidth with sufficient phase margin.VBAT Capacitor SelectionConnect 20µF capacitor to maintain charger loop sta-bility and serve as input capacitor at boost mode. Current Sense Resistor SelectionThe charging current and current limit at boost mode are inverse proportion to R SNS. Select 10mΩR SNS for proper current setting. To maintain stability of charger loop, 10mΩ or larger R SNS is recommanded.PCB Layout ConsiderationsSignal Ground and Power Ground ConnectionAt minimum, a reasonably large area of copper, which will shield other noise couplings through the IC, should be used as signal ground beneath the IC. The best tie-point between the signal ground and the power ground is at the negative side of the output capacitor on each side, where there is little noise; a noisy trace beneath the IC is not recommended.LX PinThis trace should be short, and positioned away from other weak signal traces. This node is noisy and has high voltage swing. No trace should be in parallel with it.CSIP, VBAT PinsThese pins is used as the battery voltage and inductor current feedback. The traces should be away from the noisy pins like LX. In general, the current sense resis-tor R SNS should be close to the IC.Copper Size for the LX NodeThe capacitance of LX should be kept very low to minimize ringing. It would be best to limit the size of the LX node copper.Exposed PADIt’s highly recommended to add larger copper to ex-posed PAD connected to signal ground. At high cur-rent operation, the power consumption is high. Large copper to exposed PAD decrease thermal resistance much.Package InformationSOP- 8 (FD) PackageTaping SpecificationPACKAGE Q ’TY/REELSOP-8 (FD)2,500 eaGMT Inc. does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and GMT Inc. reserves the right at any time without notice to change said circuitry and specifications.。

充电宝1a和2a的区别如今，移动电源(俗称“充电宝”)几乎成为智能手机的必备配件.那么充电宝1a和2a的区别你知道吗?下面是店铺给大家整理的充电宝1a和2a的区别，供大家参阅!充电宝1a和2a的区别1.外观上2A的要明显比1A的大;2.再就是充电快慢，理论上用2A的比1A的可缩短一半充电时间，但如果电池容量较小，用2 A 的充电器就容易损坏电池或减少寿命,一般锂电池充电电流不能超过0.5C.充电宝选购建议1.选购采用全新锂聚合物电芯和优质进口锂离子(18650)电芯制造的高信誉度品牌移动电源。

2.容量越大，体积越大。

对于数码产品较多、经常外出、对电量需求较大的朋友可选择10000毫安左右的电源，10000毫安以上的电源便携性相对较差;对于不常外出，对美观度、便携性要求较高的朋友建议选购3000-8000毫安的电源。

3.挑选一款精致美观的电源非常有必要，外观精美程度通常就是电源材质和质量的晴雨表。

充电宝质量判断的建议方法：1.在同一环境中，充满同样的电量(比如从50%到100%)，耗费时间短的充电宝比耗费时间长的充电宝质量好。

2.在同一环境中，充满同样的电量(比如从50%到100%)，外壳温度较高的充电宝质量较差。

充电宝排行榜前十名充电宝排行NO. 1、沃品"Wopow沃品"品牌，由深圳市沃品科技有限公司全权运营。

WOPOW沃品是中国最具创新精神和创新能力的数码智能电源与外设品牌，是“中国创造”的先驱和领先者。

产品通过IS09001、ISO14001、3C、CE、FCC、TLC、UL、GS等一系列国际、国内认证。

20%研发经费投入，30多项外观专利。

成为移动数码产品国内电池行业最具品牌价值企业。

充电宝排行NO.2、品胜羽博注重品质铸造未来，秉承了专注、专心、专研，从事PDA、手机、数码系列电池研发，在高容量商务电池独树一帜，拥有雄厚的技术力量，齐全的生产检测设备，产品精工制造，从原料的采购、产品的生产、检测、销售及售后服务各个环节，都严格实行全面品质监控和保障。

单芯片移动电源方案引言移动电源作为一种常见的便携式电源设备，已经成为现代人日常生活中不可或缺的物品之一。

传统的移动电源通常由多个电池芯片组成，且需要较为复杂的电路设计和布线工作。

然而，随着技术的不断进步，单芯片移动电源方案逐渐成为一种新的趋势。

本文将介绍一种创新的单芯片移动电源方案，旨在简化电路设计并提高整体性能。

背景传统移动电源采用多个电池芯片的并联或串联连接方式，但这种方案存在一些局限性。

首先，多芯片的设计需要相应的接线和电路布局，这增加了电路设计的复杂度和工作量。

其次，由于电池芯片之间的电压差异和内阻差异，可能会导致电流不稳定和能量损失。

此外，多芯片方案通常需要额外的电路保护和管理模块，以确保电池的安全性和可靠性。

设计原则为了解决传统移动电源方案的诸多问题，我们提出了以下设计原则： 1. 单芯片设计：采用单芯片集成设计，将充电、放电、保护等功能集成在一个芯片中，减少电路复杂度。

2. 高度集成化：尽可能将各个电路模块集成在芯片内部，减少外部器件数量，提高整体性能。

3. 高效能量管理：采用先进的能量管理算法和智能充放电控制策略，提高转换效率和能量利用率。

4. 安全保护机制：引入多种安全保护机制，包括过充、过放、过流和短路保护等，确保电池的安全运行。

技术实现基于上述设计原则，我们提出了一套创新的单芯片移动电源方案。

该方案采用了先进的硬件设计和智能算法，实现了高效能量管理和安全可靠的电池管理功能。

单芯片电路设计该方案使用一颗单芯片作为移动电源的主控芯片，集成了充电、放电、保护和管理等功能模块。

该芯片的引脚定义如下： - 电池接口：连接外部电池模组，提供电源供电。

- 充电接口：用于连接充电设备，实现电池的充电功能。

- 输出电接口：连接用户的消费电子设备，提供输出电源。

- 状态指示灯接口：用于显示电池的充电状态和电量，提供用户友好的使用体验。

能量管理算法该方案的能量管理算法采用了智能充放电控制策略，实现了高效能量转换和节能的功能。

TinySwitch II系列第二代微型单片开关电源的原理TinySwitch II系列是美国PI（PowerIntegrations）公司继TinySwitch之后，于2001年3月新推出的第二代增强型隔离式微型单片开关电源集成电路。

该系列产品包括TNY264P／G、TNY266P／G～TNY268P／G，共8种型号。

它特别适合制作高效率、低成本、微型化的小功率开关电源，例如手机电池充电器、PC机待机电源、彩色电视机待机电源、交流电源适配器、电机控制器以及ISDN或DSL网络终端，是体积大、效率低的线性稳压电源理想的替代品。

1TinySwitch II系列的产品分类及性能特点1.1产品分类产品分类见表1表1TinySwitch II系列产品的分类及最大连续输出功率POM1.2性能特点与第一代产品TinySwitch（TNY253～TNY255）相比，它除了保留结构简单、使用方便等优点之外，还具有以下显著特点：（1）在增加输出功率的同时，降低了芯片的功耗，使电源效率得到进一步提高。

当交流输入电压达到最大值265V，空载时芯片的功耗一般低于50mW。

TinySwitch 系列产品的最大输出功率为10W （TNY255P ／G 型），TinySwitch II 系列产品则提高到23W （TNY268P ／G 型）。

开关频率也从44kHz 提高到132kHz ，这不仅能提高电源转换效率，还允许使用低价格、小尺寸的EE13或EF12.6型磁芯，减小高频变压器的体积。

（2）增加了自动重启动计数器、极限电流状态机和输入欠压检测电路。

利用一只检测电阻来设定输入电压的欠压阈值，消除了在待机电源等应用中因输入滤波电容缓慢放电而引起的电源掉电故障。

一旦发生输出短路、控制环开路或者掉电故障，均能保护芯片不受损坏。

表2TinySwitch II 与TinySwich 的性能比较 功能 TinySwitchTNY254 TinySwitch ⅡTNY264、266～268TinySwitch Ⅱ的优点 开关频率44kHz±10％ 132kHz±6％ ①减小高频变压器的体积②提高开关电源的效率③改善稳压性能④降低开关电源成本 开关频率的温漂误差＋8％ ＋2％ 开关频率抖动量—— ±4kHz ①抑制电磁干扰②降低滤波元件成本 对由高频变压器产生的音频噪声进行衰减—— 有 有效滤除浸漆变压器的音频噪声，变压器无须采用特殊结构或胶合剂 输入欠压检测 —— 用一只电阻设定欠压阈值UUV ①保护功能更加完善②能抑制开/关噪声漏极极限电流的偏差±9.8％(25℃) ±6.8％(25℃)①提高输出功率②简化了大批量生产的制造工艺在0～100℃范围内极限电流的温漂－8％0％自动重启动——有①限制了短路输出电流，使之小于满载电流②当控制环路出现开环故障时，能对负载起到保护作用③外围电路中无须再增加元件旁路端的电压钳位保护——内部设有钳位用的6.3V稳压管允许器件从初级辅助绕组获得能量，降低了芯片的功耗所用封装的漏极防漏电距离0.94mm 3.48mm防止D S管脚之间因落有灰尘、杂物而造成高压漏电图1TinySwitch II的引脚排列（3）将TinySwitch的使能端（EN）改为双功能引出端“使能／欠压端”（EN／UV）。